Depends on how much. It doesn't make much sense to me why they would wait so long to do arguably the most time intensive work. It certainly hasn't been the case for other projects.
Keep in mind, the final two months will be very minor work and mostly a lot of testing.
It's fairly tall, but in terms of footprint the abbey building is pretty deceiving. It's only about the size of a larger McMansion, about 3600 sq ft. For comparison, 1 of the 2 ride pads on Alien Swirling Saucers (I'm not gonna use the acronym for that one) is about 5,200 sq ft.